1. Field of the Invention
This invention relates to the field of sound effect imparting devices, and in particular, to a sound effect imparting device for imparting a plurality of desired effects, such as vibrato effect and reverberation effect, to digital musical tone signals produced by an electronic musical instrument or other sound producing systems, in a simple operation using a digital memory and a digital operational circuit.
2. Description of the Prior Art
There are in prior art sound effect imparting devices for imparting sound effect such as vibrato, chorus, ensemble (symphonic chorus) and, reverberation, to musical tones produced by an electronic instrument and the like. Those prior art sound effect imparting devices, however, have a drawback in that a respective sound effect imparting circuit must be provided corresponding to each sound effect when a plurality of sound effects are imparted to a musical tone signal, with resultant in increase in the construction scale of the device.
In addition to the above drawback, since in many cases an analog delay element, such as BBD (Bucket Brigade Device) and CCD (Charge Coupled Device), is used for imparting sound effects, changing characteristics of the imparted sound effects are difficult and signal-to-noise ratio of the sound with imparted sound effects is not good. Moreover, in order to apply the sound effect imparting device to an electronic musical instrument of a type wherein musical tone signals are in the form of digital signals, the digital musical tone signals must be fed to the sound effect imparting device after converting those signals into analog signals through a digital-to-analog converter, and therefore a filter of steep cut-off characteristics is required, making circuit integration difficult, and further making the device scale larger.